The present invention relates to a slider of a closed-type compressor, and more particularly to a slider of a closed-type compressor in which friction and abrasion of an inside circumferential surface of a slider shell and an outside circumferential surface of the slider can be reduced by forming a circular are at both portions where the outside circumferential surface of the slider contacts the inside circumferential surface of the slider shell.
As shown in FIG. 1, in a conventional closed-type compressor, a rotation shaft 2 penetrates a central portion of a rotor 1 and is integrally united with rotator 1 by shrink fit.
As shown in FIG. 2, a counter balance weight 3 is combined at the upper portion of rotation shaft 2, and an eccentric crank pin 4 is fixed at a predetermined portion of the upper surface of counter balance weight 3. Crank pin 4 is associated with a slider 5. A central groove 5a having a predetermined width is formed along the outside circumference of the central portion of slider 5. At a predetermined portion of central groove 5a, a pin hole 5b for inserting crank pin 4 is formed. Also, slider 5 is enclosed by a slider shell 6 so that slider 5 reciprocates inside slider shell 6 according to the rotation of rotation shaft 2.
In the meantime, a piston 7 is welded to one side of slider shell 6. Since piston 7 is guided by cylinder 8, piston 7 linearly reciprocates inside cylinder 8 according to the rotation of the crank shaft. A frame 9 is installed around rotation shaft 2, and a plurality of oil-supplying central grooves 10 is formed on an outside circumferential surface of rotation shaft 2.
Meanwhile, as shown in FIG. 3A and 3B, in the conventional closed-type compressor, slider 5 contacting the inside circumferential surface of slider shell 6 is shaped linearly exclusive of a chamber at each end portion thereof.
When power is supplied to the conventional compressor of such structure, rotation shaft 2 which is rotatably assembled by rotor 1 by shrink fit rotates and eccentric crank pin 4 associated with counter balance 3 rotates, accordingly. Thus, slider 5 united with crank pin 4 moves forward and backward inside slider shell 6. Here, according to the forward and backward movements of slider 5, piston 7 integrally united with slider shell 6 reciprocates inside cylinder 8.
Due to a centrifugal force generated as rotation shaft 2 rotates, oil 11 (See FIG. 2) is absorbed upward along a plurality of oil-supplying central grooves 10 and supplied for lubricating friction portions between slider 5 and slider shell 6 and piston 7 and cylinder 8.
A reference numeral 30 of FIG. 4 shows a fluid pressure generated during an operation of a conventional closed-type compressor.
However, when the slider of the conventional closed-type compressor reciprocates inside the slider shell, as shown in FIG. 4, a low fluid pressure (experimental maximum value of 0.05 MPa) occurs on a lubrication surface of the slider and the slider shell. Thus, the outside circumferential surface of the slider is in direct contact with the inside circumferential surface of the slider shell, causing serious abrasion.